BRUSSELS/PARIS (Reuters) - In Tehran on Jan. 8 during a meeting with European envoys, Iranian officials abruptly stood up, walked out and slammed the door in an extraordinary break with protocol.

The French, British, German, Danish, Dutch, and Belgian diplomats in the Iranian foreign ministry room had incensed the officials with a message that Europe could no longer tolerate ballistic missile tests in Iran and assassination plots on European soil, according to four EU diplomats.

Lot - Drama - Concerns - Diplomats - Relationship

“There was a lot of drama, they didn’t like it, but we felt we had to convey our serious concerns,” one of the diplomats said. “It shows the relationship is becoming more tense,” a second said.

An Iranian official declined to comment on the meeting.

Day - European - Union - Sanctions - Iran

The next day, the European Union imposed its first sanctions on Iran since world powers agreed the 2015 Vienna nuclear arms control deal with Tehran.

The sanctions were largely symbolic but the stormy meeting encapsulated the unexpected shift in European diplomacy since the end of last year. Smaller, more dovish EU countries have joined France and Britain in a harder stance on Tehran, including considering new economic sanctions, diplomats say.

Asset - Freezes - Travel - Bans - Iran

Those could include asset freezes and travel bans on Iran’s Revolutionary Guards and Iranians developing the Islamic Republic’s ballistic missile program, three diplomats said.

The new approach moves Europe closer to U.S. President Donald Trump’s policy of isolating Iran with tough sanctions even though European governments still support the 2015 Vienna deal from which he withdrew in May.

Views - Europe - Shift - Consequences - President

Although there are diverging views in Europe, the shift could have consequences for President Hassan Rouhani’s government as it looks to European capitals to salvage that deal.

It could also strengthen anti-Western sentiment in Iran and lead to more aggressive Iranian moves around the Middle East, where the Islamic Republic is involved in proxy wars with its main regional rival Saudi...